User Manual

IDEC SmartRelay functions
IDEC SmartRelay Manual 183
• Analog comparator (actual value Ax - Ay, see Chapter
4.4.18)
• Analog trigger (actual value Ax, see Chapter 4.4.16)
• Analog amplifier (actual value Ax, see Chapter 4.4.20)
• Analog multiplexer (actual value AQ, see Chapter 4.4.26)
• Analog ramp control (actual value AQ, see Chapter
4.4.27)
• Analog math (actual value AQ, see Chapter 4.4.30)
• PI controller (actual value AQ, see Chapter 4.4.28)
• Up/down counter (actual value Cnt, see Chapter 4.4.13)
Select the required function by the block number.
Parameter p (number of
decimals)
Applies only to the Aen, Ax, 
1
and 
2
values displayed in a
message text.
Timing diagram
Q
Aen +
1
Ax
En
Aen –
2
Aen
Functional description
A 0 to 1 transition at input En saves the value of the signal at
th
e analog input Ax. This saved process variable is referred
to as ”Aen”.
Both the analog actual values Ax an
d Aen are multiplied by
the value at parameter A (gain), and parameter B (offset) is
then added to the product: 
(Ax•gain) + offset = Actual value Aen, when input En
chan
ges from 0 to 1, or
(Ax•gain) + offset = Actual value Ax.
Output Q is set when the signal at input En = 1 and if the
actual valu
e at input Ax is out of range of
Aen -
2
to Aen + 
1
.
Output Q is reset, when the actual value at input Ax lies
wit
hin the range of
Aen -
2
to Aen+ 
1
, or when the signal at
input En changes to lo.